Finding the Fourth Proportional to 1,086.69, 1,630.17 and 393.27

Step by Step Solution

1. Step 1: Write the proportion equation
   1,086.69 : 1,630.17 = 393.27 : x
2. Step 2: Convert to fraction form
   1,086.69/1,630.17 = 393.27/x
3. Step 3: Cross multiply
   1,086.69x = 1,630.17 × 393.27
4. Step 4: Simplify right side
   1,086.69x = 641,096.96
5. Step 5: Solve for x
   x = 641,096.96/1,086.69
6. Step 6: Final answer
   x = 589.95